Conversion Disorder, Guillain-Barré Syndrome, or Neurologic Lyme Disease?

Neurologic symptoms that worsen despite psychiatric treatment rarely prompt infectious disease testing—even when a patient presents with progressive paralysis and urinary incontinence.

Neurologic Lyme disease can mimic several conditions—including autoimmune disorders, psychiatric illness, and peripheral neuropathies—making diagnosis particularly challenging in atypical cases.

Teodoro and colleagues describe a case that illustrates this diagnostic pattern: a 62-year-old woman initially treated for conversion disorder who was later diagnosed with Guillain-Barré syndrome, possibly triggered by neurologic Lyme disease.

Conversion disorder is a mental health condition in which symptoms such as blindness, paralysis, or other neurologic deficits cannot be explained by standard medical evaluation.

For a broader discussion of how neurologic Lyme disease can be mistaken for other conditions, see
Lyme Disease Misdiagnosis: Why It Happens and What Patients Need to Know.

Initial Presentation and Early Dismissal

A 62-year-old woman presented to the emergency department with weakness in her left hand and both legs, which resulted in two consecutive falls with head trauma. Initial testing was normal, and she was discharged.

The following day her symptoms worsened. She returned to the hospital with significant motor impairment—an inability to walk independently—and urinary incontinence.

Neurologic examination revealed asymmetric tetraparesis, hyporeflexia, doubtful hemihypesthesia, and a left extensor plantar reflex.

Tetraparesis refers to weakness affecting all four extremities. Hemihypesthesia refers to decreased sensation on one side of the body.

Conversion Disorder Diagnosis

Clinicians initially suspected conversion disorder based on several features of the presentation:

• Absence of a typical neurologic pattern
• Positive Hoover sign during early evaluation
• Inconsistent and fluctuating motor deficits
• Recent stressful life events
• Underlying anxiety

The patient reported a recent stressful event and symptoms of anxiety. She was prescribed sertraline (100 mg) and pregabalin (150 mg).

However, by day five her condition had worsened. Neurologic examination now showed areflexia in both upper and lower limbs.

Needle electromyography revealed a subacute motor axonal neuropathy pattern and right median nerve mononeuropathy.

Guillain-Barré Syndrome

Based on EMG findings and cerebrospinal fluid analysis, physicians considered Guillain-Barré syndrome.

The spinal tap showed albuminocytologic dissociation, a classic finding in Guillain-Barré syndrome.

Guillain-Barré syndrome typically develops after infections such as Campylobacter, influenza, or other viral illnesses. When these common triggers are absent, clinicians may consider alternative infectious causes—including Borrelia infection.

Treatment with intravenous immunoglobulin (0.4 g/kg/day for five days) was initiated and resulted in partial improvement in motor function.

Lyme Disease Diagnosis

Further testing revealed evidence of Lyme disease. The patient had positive IgM titers for Borrelia burgdorferi, and repeat cerebrospinal fluid testing showed elevated mononuclear white blood cells (20/μL) along with Borrelia antibodies.

Importantly, none of the most common infectious triggers of Guillain-Barré syndrome were identified.

As Teodoro notes, “Surprisingly, serologies for Borrelia were positive, with further detection of IgM Borrelia antibodies in cerebrospinal fluid.”

The authors conclude that Guillain-Barré syndrome triggered by Borrelia infection should be considered in unusual neurologic presentations.

The patient was treated with intravenous ceftriaxone (2 g/day) for 14 days and showed significant improvement in motor function. However, she required ongoing rehabilitation and physical therapy.

Why This Pattern Matters

This case is not unique. Guillain-Barré syndrome has previously been misdiagnosed as conversion disorder, highlighting how atypical neurologic presentations can be misinterpreted as psychiatric conditions.

Although uncommon, neurologic Lyme disease can mimic Guillain-Barré syndrome and other neurologic disorders.

Early neurologic Lyme disease can produce symptoms that fluctuate or appear inconsistent, which sometimes leads clinicians to consider functional neurological disorders or psychiatric explanations before infectious causes are evaluated.

Clinical Takeaway

Progressive neurologic symptoms that worsen despite psychiatric treatment should prompt further neurologic and infectious disease evaluation, particularly in Lyme-endemic regions.

This case illustrates how a diagnosis of conversion disorder can delay recognition of both Guillain-Barré syndrome and the underlying Borrelia infection.

Objective testing—including EMG, spinal fluid analysis, and Lyme serologies—may reveal treatable infectious causes even when early presentations appear psychiatric.

Early recognition matters. In this case, the patient ultimately required both immunoglobulin therapy for Guillain-Barré syndrome and antibiotic treatment for Lyme disease.

These diagnostic challenges are discussed more broadly in the guide to Lyme disease symptoms, where neurologic complications are among the most frequently overlooked presentations.

Frequently Asked Questions

Can Lyme disease cause Guillain-Barré syndrome?

Yes. Guillain-Barré syndrome can develop as a post-infectious complication of Lyme disease, though this is rare. Borrelia infection can trigger autoimmune responses affecting the peripheral nervous system.

Why was this patient initially diagnosed with conversion disorder?

Her symptoms included inconsistent motor deficits, recent stressful life events, and anxiety—features often attributed to conversion disorder. However, these factors can also coincide with neurologic illness.

How was the correct diagnosis eventually made?

Progressive worsening despite psychiatric treatment, EMG findings showing nerve damage, and spinal fluid analysis revealing Borrelia antibodies led to the diagnosis of Lyme-triggered Guillain-Barré syndrome.

What symptoms distinguish Guillain-Barré syndrome from conversion disorder?

Guillain-Barré syndrome typically shows progressive weakness, areflexia (absent reflexes), and objective findings on EMG and spinal fluid analysis. Conversion disorder symptoms are inconsistent and cannot be explained by neurological testing.

How common is neurologic Lyme disease misdiagnosis as a psychiatric condition?

Neurologic Lyme disease is frequently misdiagnosed as psychiatric illness, particularly when symptoms include cognitive changes, mood disturbances, or atypical neurologic presentations.

Related Reading

• Lyme Disease Misdiagnosis: Why It Happens and What Patients Need to Know
• Lyme Disease Manifests as Autoimmune Disorder: Sjögren’s Syndrome
• Can Lyme Disease Trigger an Autoimmune Disease?
• Lyme Disease Mimics Autoimmune Disorder in Elderly Woman

References

1. Teodoro T, Oliveira R, Afonso P. Atypical Lyme Neuroborreliosis, Guillain-Barré Syndrome or Conversion Disorder: Differential Diagnosis of Unusual Neurological Presentations. Case Rep Neurol. 2019.
2. Edelsohn G. Guillain-Barré misdiagnosed as conversion disorder. Hosp Community Psychiatry. 1982.
3. Tyagi N, Maheswaran T, Wimalaratna S. Neuroborreliosis: the Guillain-Barré mimicker. BMJ Case Rep. 2015.

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Dr. Daniel Cameron, MD, MPH
Lyme disease clinician with over 30 years of experience and past president of ILADS.

Symptoms • Testing • Coinfections • Recovery • Pediatric • Prevention